| 摘要 |
<p>724,929. Injectors. UNION CARBIDE & CARBON CORPORATION. Feb. 6, 1953 [Feb. 9, 1952], No. 3344/53. Class 71. [Also in Group VI] In a device for mixing two gases, a high pressure oxygen is supplied through the'nozzle of an injector and the area of the throat, through which a lower pressure gas is drawn, is variable in response to the pressure of the first mentioned gas. The apparatus described concerns the mixing of air and oxygen for respiratory equipment. Oxyger is supplied through a stop valve 15 to the centre bore 16 of an injector nozzle 17. Air is thereby drawn in through a port 21 and through a throat 18 in a tubular member 26, whence the mixture is passed to the patient. The nozzle 17 is formed in one piece with a piston 23 and oxygen pressure, acting through a duct 22, bears on the upper side thereof in opposition to a coil spring 25. Consequently, with increased oxygen pressure, and thus rate of flow, the nozzle is moved' downwards against the spring 25, thereby reducing the effective throat area and the proportion of air entrained. The parts are so dimensioned that the total flow of mixture remains constant, only the proportions changing. The total volume supplied to the patient may be adjusted by altering the axial position of the throat member 26. In modified forms, see Figs. 7 and 8 (not shown) the throat member is also made movable under the influence of the applied oxygen pressure, by being mounted on a piston, the movement of which is controlled by the oxygen pressure in opposition to a spring. By using springs of different strengths the relative movement of nozzle and throat may be varied and the proportion of constituents in the resultant gas mixture consequently changes in a non-linear manner with respect to the oxygen pressure.</p> |
